The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
A manual transmission drivetrain includes an internal combustion engine (ICE), a clutch and a manual transmission. The clutch engages with a flywheel on the ICE and transfers torque output of the engine to the manual transmission. Torque transfer from the ICE to the transmission is interrupted when a vehicle operator manually shifts between gears of the transmission. During a gear shift event, the clutch is disengaged (i.e. the ICE is disengaged from the transmission), a desired gear is manually selected, and the clutch is reengaged.
A dual-clutch transmission (DCT) drivetrain includes an ICE and a DCT (or semi-automatic transmission). The DCT includes two clutches, inner and outer transmission shafts, and two gear sets with respective gear shafts and/or lay shafts. As an example, the inner transmission shaft may be associated with a first gear set and controlled using a first clutch. The outer transmission shaft may be associated with a second gear set and controlled using a second clutch. The first gear set may include first, third and fifth gears. The second gear set may include second, fourth and sixth gears. By using two transmission shafts, a DCT drivetrain can provide uninterrupted torque transfer between the ICE and an output shaft of the DCT during gear shifts. This decreases shift times and improves fuel economy.
The DCT includes a type of energy storage device in the form of a hydraulic fluid (oil) accumulator which holds fluid under pressure until it is needed to cause the engagement of either the inner or outer clutch during a gear shift. The accumulator enables the hydraulic pressure system of the DCT to cope with extremes of demand using a less powerful pump, to respond more quickly to a temporary demand, and to smooth out pulsations.
An oil pressure sensor is in fluid communication with the hydraulic fluid accumulator for monitoring the oil pressure of the hydraulic system. It is appreciated that the fluid pressure of the hydraulic system has a direct impact on the timing and operation of shifting the transmission into a higher or lower gear when needed. Hydraulic pressures that are too high or too low can lead to during shifting can lead to the transmission working incorrectly and potentially causing damage to internal components during the shifting process. The transmission oil pressure sensor provides the means for detecting when hydraulic pressures are improper thus allowing the vehicle operator to be alerted to when service is needed. Thus, it is important to have a reliable means to determine if the oil pressure sensor has failed, or if the data being received from the sensor is inaccurate such that replacement is required.